Central pain: "new" syndromes and their evaluation

Area of Science:

• Neurology
• Pain Medicine
• Neuroscience

Background:

• Central pain syndrome (CPS) is pain resulting from a lesion in the central nervous system (CNS).
• CPS is characterized by low incidence but is often intractable and lacks effective treatments.
• The precise etiology of CPS is speculative.

Purpose of the Study:

• To investigate the sensory abnormalities associated with central pain syndrome.
• To identify the specific neurological pathways involved in the development of CPS.
• To understand the relationship between lesion severity and the manifestation of CPS.

Main Methods:

• Review of clinical data and neurological examinations of patients with suspected central pain.
• Analysis of sensory pathway involvement, focusing on spinothalamocortical and dorsal column/medial lemniscus systems.
• Correlation of lesion characteristics with reported pain symptoms and sensory deficits.

Main Results:

• A common sensory abnormality in CPS is the interruption of spinothalamocortical nociceptive pathways.
• Severe CNS lesions with total destruction of ascending sensory systems do not typically result in CPS.
• Mild to severe disruption of the anterolateral ascending system, with preserved dorsal column/medial lemniscus function, is frequently associated with CPS.
• Dysesthesias and pain in CPS can be triggered by afferent input to the large fiber system, even during remission, and may persist after deafferentation.

Conclusions:

• Interruption of spinothalamocortical pathways is a key feature of central pain syndrome.
• The degree of disruption in ascending sensory systems, particularly the anterolateral system, is critical in CPS development.
• Preservation of dorsal column/medial lemniscus function appears important for CPS manifestation.
• Established central pain can be persistent and difficult to treat, even with further neurological interventions.